Investigation and molecular mimicry of the antigen involved in the interaction between the monoclonal antibody 5D10 and the human breast cancer cell line MCF-7

✍ Scribed by Caroline Vandevyver; Stéphane Canarelli; Claudia Bossen; Igor Fisch; Kris Motmans; Jef Raus; Ruth Freitag

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 328 KB
• Volume: 97
• Category: Article
• ISSN: 0006-3592
• DOI: 10.1002/bit.21276

✦ Synopsis

Abstract

Monoclonal antibody (mAb) 5D10 is directed against the human breast cancer cell line MCF‐7. Biochemical characterization of the antibody epitope was attempted and revealed a complex, most likely carbohydrate‐linked nature, which prevented isolation and further studies of the interaction. A major goal of this work was to generate structural mimics of the 5D10 epitope to serve as putative substitutes in such studies. A peptide library displayed on filamentous phage was used to select for mimotope peptide sequences. All positive phage clones selected from the library displayed the amino acid sequence H~2~NQMNPMYYRCO~2~H. This peptide sequence, as well as a branched form of the peptide, was found to bind mAb 5D10. Moreover, both peptide sequences were able to inhibit the binding of 5D10 to the MCF‐7 cells in a concentration‐dependent manner, with an EC~50~ value in the range of 65 µM. According to these results, random phage peptide libraries can serve to identify mimotopic peptides for unknown complex cell surface epitopes. Biotechnol. Bioeng. 2007;97: 721–734. © 2006 Wiley Periodicals, Inc.